I've had a F2a for almost 31 years. I could take it out tonight and run a roll through it and still get acceptable images. It is very tired, and in need of a complete overhaul.
In 1983 I flew to Panama for military training. During the flight some how the meter switch was left on and on arrival I found the batteries had died. Fellow soldiers laughed that I was "not going to get picture" because of "without batteries how" type of thinking.
I shot film for two weeks before getting to town to buy some batteries... every image that I shot came out. I think I shot some HP4 - Pan F or something that was a 72 exposure roll....
SO.. for complete manual control I stick with the F2 series and just remember the "Sunny 16 rule"....